1. Technical Field
The present invention relates to an image writing/display device and an image writing/display method.
2. Related Art
There are proposed devices that display images as follows: a cholesteric liquid crystal layer is a display layer, and by applying driving voltage between a pair of electrodes, the orientation pattern of the cholesteric liquid crystal layer is changed to a focal conic phase (F phase), a planar phase (P phase), a homeotropic phase (H phase).
High reflectance and low driving voltage are always demanded of devices using a cholesteric liquid crystal layer. Note that, although there are various required reflectances and driving voltages depending on the environments, conditions and specifications that are applied, high reflectance generally means greater than or equal to 40%, and low driving voltage generally means less than or equal to 40 V.
Here, in a cholesteric liquid crystal layer, in a case in which all of the orientation changes are provided by applying driving voltage, the reflectance and the driving voltage are in a substantially linear relationship (proportional relationship) with the thickness of the cholesteric liquid crystal layer. Accordingly, when attempting to obtain a sufficient reflectance, the thickness of the cholesteric liquid crystal layer becomes thicker, and the driving voltage becomes higher.
Other than driving voltage, pressure and temperature are ways of controlling the orientation of the cholesteric liquid crystal layer.